A plasma display panel is a component in which a mixed gas for electric discharge use such as neon (Ne), xenon (Xe) or the like is filled in a discharge space sandwiched between two sheets of glass substrates, an electric discharge is allowed to occur by applying a voltage greater than that necessary to initiate the electric discharge between electrodes and a phosphor formed above a substrate is excited to emit light by ultra violet rays generated by the electric discharge so as to serve as a display. The plasma display device is expected as a display device capable of realizing a future full-color large screen display device owing to the superiority over a display area, a display capacity, and response characteristics, etc. In addition to that, a large screen of 40 inch to 60 inch or more in size is now realized as a direct view type display, which cannot be realized with other devices. The plasma display device has a disadvantage of occurring deterioration of electronic parts due to heat when a temperature in the device gets high.